<template>
  <div id="app">
    <h1>第八题 - 学生信息</h1>
    <div>
      <span>姓名:</span>
      <input type="text" v-model.trim="name"/>
    </div>
    <div>
      <span>年龄:</span>
      <input type="number" v-model.number.trim="age"/>
    </div>
    <div>
      <span>性别:</span>
      <select v-model="sex">
        <option value="男">男</option>
        <option value="女">女</option>
      </select>
    </div>
    <div>
      <button @click="add">添加/修改</button>
    </div>
    <div>
      <table
        border="1"
        cellpadding="10"
        cellspacing="0"
      >
        <tr>
          <th>序号</th>
          <th>姓名</th>
          <th>年龄</th>
          <th>性别</th>
          <th>操作</th>
        </tr>
        <tr v-for="(item,index) in list" :key="item.id">
          <td>{{item.id}}</td>
          <td>{{item.name}}</td>
          <td>{{item.age}}</td>
          <td>{{item.sex}}</td>
          <td>
            <button @click="del(index)">删除</button>
            <button @click="btn(index)">编辑</button>
          </td>
        </tr>
      </table>
    </div>
  </div>
</template>
<script>
export default {
  data () {
    return {
      list: [
        {
          id: 1,
          name: "Tom",
          age: 19,
          sex: "男"
        },{
          id: 2,
          name: "Jone",
          age: 21,
          sex: "女"
        }
      ],
      name:'',
      age:'',
      sex:'',
      abc: false,
      index: null
    }
  },
  methods: {
    add(){
      if (this.abc) {
        this.list[this.index].name = this.name
        this.list[this.index].age = this.age
        this.list[this.index].sex = this.sex
        return
      }else if(!this.name || !this.age || !this.sex){
        return alert('必填项不能为空')
      }else{
        this.list.push({
          id:this.list.length+1,
          name:this.name, 
          age:this.age, 
          sex:this.sex
        })
        this.name = this.age = this.sex = ''
      }
    },
    del(i){
      this.list.splice(i,1)
    },
    btn (i) {
      this.abc = true
      this.index = i
      this.name = this.list[i].name
      this.age = this.list[i].age
      this.sex = this.list[i].sex
    }
  }
}
</script>
<style>

</style>